Elevator safety device.



A. C. SMITH.

ELEVATOR SAFETY DEVICE.

APPLlCATlON man SEPT. 15. 1911.

LM8,%% Patentfliuly 33 1 915.

R571 m /M g o /0 2X) 40%: Z MKM. A MW Mfl% @EQ/MW A. C. SMITH.

ELEVATOR SAFETY DEVICE.

APPLICATION FILED SEPT. 15. 1911.

Patented July 27, 1915.

4 SHEETS-SHEET 2.

A. C. SMITH.

ELEVATOR SAFETY DEVICE. APPLICATION n'uzu SEPT. 15. 191 i.

Patented July 27, 1915.

4 SHEETS-SHEET 3.

wi haeo oco:

fim {$24 www- COLUMBIA I'LANOGRAI'H c0.. WASHINGTON, D c.

A. 0. SMITH,

ELEVATOR SAFETY DEVICE.

APPLICATION FILED SEPT. l5. l9! 1.

- LM&%% Patented July 27,1915.

4 SHEETS-SHEET 4.

PATENT OFFTFE.

ALLEN C. SMITH, 0F YOINKERS, NEW YORK, ASSIGNOR T0 OTIS ELEVATORCOMPANY, OF JERSEY CI'IY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

ELEVATOR SAFETY DEVICE.

Application filed September 15, 1911.

To all whom it may concern Be it known that I, ALLEN O. SMrri-I, acitizen of the United States, residing at Yonkers, in the county ofWestchester and State of New York, have invented a new and usefulImprovement in Elevator Safety Devices, of which the following is aspecification.

My invention relates to safety devices for elevators and moreparticularly to such safety devices as have jaws located on the car andwhich are adapted to grip the guide rails when the car travels at anexcessive rate of speed or when it is desired for any purpose to applythe safety device.

One of the objects of my invention is the provision of means foreffecting the simultaneous operation of the gripping jaws to engage theguide rail when the car travels at an excessive rate of speed or when itis desired for any reason to apply the jaws to the rail.

Another object is to facilitate the application and removal of thesafety device from the car when the latter is in the hatchway.

A further object of my invention is the provision of means which aresimple in construction, easily installed and free from lost motion.

It has been found in practice that in safety devices of this type thereare several imperfect features. One of these features is the tilting ofthe elevator car caused by the failure of the gripping jaws to grip theguide rails with equal pressure on both sides of the car. This unequalpressure of the gripping jaws is due to the failure of the jaws tooperate simultaneously, as by lost motion, for instance, in several ofthe parts, or any way, to the failure of the jaws to operatesimultaneously to engage the guide rails, but in my device Iovercome'this' objectionable feature by providing an arrangement inwhich there is no lost motion; and which effects the simultaneousoperation of the jaws to engage the guide rails.

On installing and repairing a safety device of this type, it has beenfound necessary on account of lack of space in the hatchway to out holesin the sides of the hatchway in order to install or remove broken parts,such as in a case where a rod or shaft is used to connect the two setsof gripping jaws, but in my device I overcome the above men-Specification of Letters Patent.

'rod f. When the car O Patented July 27, 1915. Serial No. 649,519.

tioned objectionable features by a compact arrangement of parts whichareeasily i11- stalled and replaced and are also free from lost motion.

Referring to the drawings, Figure 1 diagrammatically illustrates theapplication of my device in an elevator system. Fig. 2 is a sideelevational view of the gripping jaws and a safety plank. Fig.v 3 is apart sectional plan view of Fig. 2. Fig. 4; is a side elevation showinga portion of the top of an elevator car with a device attached theretowhich is connected to a governor rope to operate the gripping jaws. Fig.5 is a plan view of Fig. 1. Fig. 6 is an elevational view of one of thesegmental gears, taken on the line 8, s, Fig. 3, looking in thedirection of the arrows.

In describing. my device it will be neces sary only to describe theparts on one side of the car, since the parts are the same on bothsides, with the exception hereinafter noted- Referring now to Fig. 1, amotor, M, is

directly connected by means of a shaft 1 to a hoisting apparatus P,which is connected to a car O and counterweight W by means of a cable 3,passing over sheaves, 4, 5 and 6, mounted on a beam N. A brake R of awell known type is shown. The governor-rope 7, is adapted to run withthe car O, and has both of its ends secured to a double-eyerope-fastener 8 which is secured to a lever 9. The governor rope runs upand over a sheave 10 which is preferably situated above the upper limitof the cars travel, thence down and under a sheave 11 near the lowerlimit of the cars travel. The sheave 11 may be provided with weights 12which will serve the purpose of keeping the governor rope 7 at a propertension. A speed governor K of a well known type is shown, having jaws,e, operated through a attains a'predetermined speed the governor ropeoperates its jaws, 6, through the rod 7, to'grip the rope 7, therebycausing the safety device to operate. A further description of thelatter will be given later.

Referring now to Figs. 2 and 3, a portion of two channel beams, A, isshown, which forms a part of the framework of the car O. A safety block13 is secured to the bottom of each beam by bolts 14:, 14, and consistsof a respective shafts 19 in the journal bearings E by the pins 20. Thegripping jaws are provided with teeth 18 which insures a suitablegripping effect of the jaws to the guide rails G. The shaft 19 extendsthrough the'bearing E and into a hub 22 of a segmental gear 21, thelatter being secured to the shaft 19 by a pin 23. A shaft 19 extendsthrough a bearing E and supports a jaw on one end and a segment gear 21on theiother end, secured thereto by a rivet 2f, the two gears 21 and 21intermeshing with each other. The gear 21, Fig. 6, has a hub 22 which issocketed or recessed as at 25, to receive the end of a cross-bar 26. Therecess and end-of the bar are angular in corresponding crosssection toeach other and the end of the bar snugly fits the recess. The wall ofthe hub is split or has an entry to the recess 25, the end of-the bar tobe transversely entered therethrough to reach the recess. Thereare bolts27 to retain the end of the bar orlshaft in the recess. It is plain thatthe recess and the end of the bar might beround, and a set screw be usedto effect an engagement between the two parts to hold the bar fromturning in the recess; or some other kind of coupling be used. The bar26 connects the segmental gears 21 and the shafts of two of the jaws,one jaw on each side, of the car. The bar secures and insures thesimultaneous movement of the two jaws,

and through the intermeshing gears, the simultaneous movement of all thejaws. This arrangement secures an equal pressure of the jaws, and oneachside of the car, and thereby provides against the car being tilted uponbeing arrested in its motion by the safety device, .since the jaws movetogether to grip the guides. I have divided the shaft, which usuallyextends across the car and supports the jaws, into three parts, andjoined them together at their ends by means of the coupling socket orrecess. This division enables me to withdraw the bar transversely of itslength instead of endwise, and thereby avoids the necessity of cutting ahole in the side of the hatchway through which to permit the endwisewithdrawal of the bar and the corresponding removal of the jaws andgears, and other parts of the safety device. This feature is of signaladvantage and will be readily appreciated, since heretofore with anintegral or one-piece bar, great difliculty and expense have beenincurred to get at the parts to remove and replace worn or broken parts.

A red 28 is pivotally connected to one gripping jaw 18 by a bolt 17, andthis red extends upwardly and is suitably secured to a lever 9 of theinterlocking device 1*]. In the diagrammatic representation of thedevice shown in Fig. 1, the rod 28 is pivoted to the lever 9 at a pointsomewhat removed from the end of the lever merely for the sake ofclearness of illustration. 1n the actual construction of the device, Iprefer to pivot the rod 28 as shown in Figs. 4 and 5, in which the rodlies in a slot 30 in the lever 9 and is provided with a convex washerand nut as shown, so as to prevent cramping of the red when the lever 9is swung upon its pivot. The interlocking device is mounted on thechannel-beam J at the top of the car C. The interlocking device Hconsists of a lever 9 pivotally supported on a stud 31 which extendsthrough the channel beams J. The slot 30 is to allow a free movement ofthe rod 28, when the lever 9 is moved. The double eye rope fastener S issecured on the lever 9 by the bolt 32 and has the two ends of thegovernor rope 7 secured thereto. A bracket 33 is secured to the beam Jby bolts 34, and is formed with lugs through which extends a pivot rod37. Mounted on the rod 37 is a detent lever 36, the upper end of whichis formed with a rounded knob or detent adapted to engage acorresponding recess 39 formed in the lever 9. The detent lever is heldin engagement with the lever 9 by means of a coil spring 38 mounted on arod 38 having a screw-threaded connection with the bracket 33. Thespring 38 bears at its opposite ends against the detent lever and awasher 29' on the rod 38. The detent 36 holds the lever 9 in its normalposition with a yielding pressure and prevents said lever from beingoperated by any slight pull on the governor cable 7, but will relieve orrelease said lever when the cable is gripped by the governor K.

I will now describe the operation of my device :Under usual conditionsthe elevator car C will run up and down over the guides G and in doingso will carry the governor rope 7 with it. This will cause the speedgovernor K to be rotated at a speed proportional to that of the car. Iffor any reason the speed of the car in its downward travel becomesexcessive, the speed governor K will then raise the governor rod 7" tosuch a degree as to cause the clamping jaws'e to be quickly andpowerfully drawn against the governor rope 7. This will arrest themovement of the governor rope and will cause it to pull the lever 9upwardly, the pull on the rope 7 overcoming the action oftheinterlocking spring-pressed detent 36 which normally locks the lever9, thereby holding the safety-device on the bottom of the car C in itsnormal position. The rod 28 which directly connects the lever 9 and thegripping jaw 18, will be pulled upwardly with the lever 9, therebycausing the two sets of gripping jaws simultaneously to engage with theguide rails G to arrest the movement of the car C. It will be seen thatthe initial upward pull on the rod 28 is sulficient to bring the teethon both sets of gripping jaws into engagement with the guide rails. Thedownward movement of the car will cause the gripping jaws to be furtherrotated, thereby causing the gripping teeth to engage deeper into theguide rails thereby giving a powerful gripping effect. A great strain isbrought to bear upon the shafts which support the gripping jaws and alsothe connecting shaft or bar 26, when the grip dogs are in operation, butto overcome this I provide stops 40 on both safety blocks which limitthe upward movement of the gripping jaws and relieve the strain fromtheir connecting parts.

It will be seen with my device it will be impossible to get an unequalapplication or pressure of both sets of the gripping jaws to the guiderails, which would tend to tilt the car, because as soon as the rod 28is pulled it imparts the same motion through the shaft 26 to the set ofgripping jaws on the other side of the car, the meshing segmental gearsassuring the simultaneous operation of the gripping jaws to engage theguide rails with a quick and equal pressure.

In Fig. 1 I have shown an arrangement whereby the safety device may beoperated manually from the car if for any reason it may be foundnecessary. For this purpose a rope 4:1 is secured to the end 42 of thelever 9, and is adapted to be pulled downwardly by hand, therebyreleasing the lever 9 from engagement with the interlocking detent 36.The upward movement of the opposite end of the lever 9 causes the safetydevice to operate the gripping jaws in the manner as has been describedheretofore.

lVhile I have disclosed in detail the various parts, I wish not to beconfined to the details disclosed, but to have the benefit of allequivalents to which I may be entitled.

Having thus described my invention,

Copies 01' this patent may be obtained for five cents each, byaddressing the what I claim and desire to secure by Letters Patent is 1.In an elevator or hoisting apparatus, a safety device comprising sets ofpivotally supported gripping jaws, intermeshing gears for each set, oneof the gears of each set having a socket or recess angular incross-section and split to allow the entry to the socket of a bar, a barhaving an end angular in cross-section to correspond to thecross-section of the socket, the locking means to hold the jaws in aninoperated position, means connecting the jaws and the locking means,and means for releasing the locking means to efiect the simultaneousoperation of the jaws to engage the rails, substantially as described.

2. A safety device for a hoisting apparatus, comprising a jaw, a socketor recess part secured to the jaw, a jaw bar, the socket having an entrythrough its wall, adapted to allow the end of the jaw bar to be passedtherethrough into the socket or recess.

3. A safety device for a hoisting apparatus, comprising a jaw, a socketor recess part secured to the jaw, the socket being angular incross-section and having an entry or split through its wall, a jaw barhaving its end angular in cross section to correspond to the crosssection of the said socket, to allow the end of the jaw bar to be seatedinto the socket or recess.

4. A safety device for hoisting apparatus, comprising two simultaneouslyoperable oppositely opposing jaws on either side of the car,intermeshing gears for each set, one of the gears of each set having asocket or recess angular in cross section and split to allow the entryto the socket of a bar, and a bar having ends angular in cross-sectionto correspond to the cross section of the socket.

In testimony whereof, I have signed my name to this specification in thepresence of two subscribing witnesses.

ALLEN 0. SMITH.

Witnesses:

F. O. DU'r'roN, GEORGE D. Rosn.

Commissioner of Patents,

Washington, D. G.

